Hitless redundancy protection for line differential protection communcations with active multipath pseudowire over IP/MPLS

Line differential protection systems (87L) has stringent communication requirements, including low latency, symmetric delay, jitter mitigation, and high resilience. Building on the capabilities of IP/MPLS networks, which provide deterministic quality of service (QoS), flexible playout buffers for jitter control, and techniques to minimize delay asymmetry, this paper introduces an innovative solution: active multipath pseudowires. By replicating relay traffic over multiple active pseudowire paths over IP/MPLS networks, this technology significantly enhances network reliability with hitless recovery and multi-fault resilience. This paper also presents the results of an industry validation effort, demonstrating how modern IP/MPLS networks can meet the utmost reliability and availability standards required for line differential protection, thereby ensuring grid resiliency and availability.